#include <bits/stdc++.h>
#include <atcoder/modint.hpp>
using namespace std;

using i32 = int;
using i64 = long long;
using i128 = __int128_t;
using f64 = double;
using p2 = pair<i64, i64>;
using p3 = tuple<i64, i64, i64>;
using mint = atcoder::modint998244353;
constexpr i64 inf = 1e18;

void _main();
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  cout << fixed << setprecision(18);
  _main();
}

void _main() {
  i64 n, m, k;
  cin >> n >> m >> k;
  vector<vector<p2>> g(n);
  for (i64 i = 0; i < m; i++) {
    i64 u, v, t;
    cin >> u >> v >> t;
    u--, v--;
    t %= k;
    g[u].push_back({v, t});
    g[v].push_back({u, t});
  }
  vector<i64> dp(n, -1);
  auto dfs = [&](auto dfs, i64 v) -> void {
    for (auto [nv, t] : g[v]) {
      if (dp[nv] == -1) {
        dp[nv] = dp[v] + t;
        dfs(dfs, nv);
      }
      i64 d = abs(dp[nv] - dp[v]) + t;
      k = gcd(k, d);
    }
  };
  dp[0] = 0;
  dfs(dfs, 0);
  cout << dp[n - 1] % k << "\n";
}